Arylacetic acids and esters are widely used in the chemical industry as intermediates for many products. Phenylacetic acid in particular may be prepared by the conversion of benzyl chloride to the cyanide which, upon hydrolysis, is converted to the acid which may be converted to the desired ester. This process, however, is undesirable inter alia in that it is characterized by danger to personnel who must utilize special precautions when handling cyanides.
Other approaches to the preparation of phenylacetic acid (U.S. Pat. No. 3,708,529) include the carbonylation of benzyl chloride at 20.degree. C.-80.degree. C. and atmospheric pressure utilizing a catalyst mixture containing (i) a cobalt salt such as CoCl.sub.2, (ii) an iron-manganese alloy, and (iii) a sulphurated promoting agent such as sodium thiosulfate.
U.S. Pat. No. 3,928,429 discloses a similar reaction at 30.degree. C.-70.degree. C. in the presence of a cobalt or iron carbonyl plus water and an alcohol.
U.S. Pat. No. 4,034,004 discloses use of a catalyst system containing (i) a palladium or phosphine-palladium component, and (ii) a quaternary alkyl ammonium salt--typically tetrabutyl ammonium iodide and Pd[P(C.sub.6 H.sub.5).sub.3 ].sub.4.P(C.sub.6 H.sub.5).sub.3.
U.S. Pat. No. 4,128,572 discloses use, in diphase system, of catalyst system containing (i) a quaternary alkylammonium salt and a cobalt hydrocarbonyl salt.
Prior art techniques yield little or no ester product and if the ester is the desired product, it is necessary to separately esterify the acid.
It is an object of this invention to provide a process for direct preparation of esters of acids such as phenylacetic acid. Other objects will be apparent to those skilled in the art.